Vent value



A ril 22, 1 969 H. M, BLANCHETTE ET AL 3,439,697

VENT VALVE Filed April 2 1966 FIG. I.

INVENTORS HOWARD M. BLANCHETTE WILLIAM R. OSBAN AGENT 3,439,697 VENTVALVE Howard M. Blanchette, Pensacola, and William R. Osban, GulfBreeze, Fla., assignors to Monsanto Company, St. Louis, Mo., acorporation of Delaware Filed Apr. 26, 1966, Ser. No. 545,368 Int. Cl.F16k /00; G05d 7/00 US. Cl. 137-119 2 Claims ABSTRACT OF THE DISCLOSUREA vent valve having a longitudinally fluted valve member slidablyoperable within a bore formed in the valve housing and being exposed atthe fluid inlet end of the bore to pressure of fluid that isrestrictively vented or bled to atmosphere through passages formed inthe valve housing and valve member when the latter is biased to a closedor seated position. When the valve member is unseated to an openposition by a build-up of fluid pressure in the inlet end of the borethe passages are disconnected and fluid flows past the fluted valvemember.

In some manufacturing processes conditions require alternate supply andcut-off of a gas, as steam or air under pressure, to a processing zone.A typical example is in the processing of nylon filaments and yarns. Inconditioning certain types of yarns, the yarns are passed through aconditioning tube filled with steam. In conditioning other types ofyarns it is necessary to cut-off the delivery of team to theconditioning tube. In controlling the delivery and cut-off of steam tothe conditioning tube by conventional valve means, the latter meanssometimes leak when in a shut-01f position and permit steam to seep orescape therepast. The fugitive steam seeping to the conditioning tubeoften adversely affects the processing of yarns that do not requiresteam conditioning. Another example in the textile industry where it isimportant not to have fluid seep by a valve is in the use of a venturitube employed to string-up yarns. The yarn is sometimes passed through aventuri tube having air under pressure delivered thereto to keep theyarn end moving from one position to another. After the string-up isaccomplished, the flow of air under pressure to the venturi tube iscut-off. However, in this example, air under pressure often seeps pastvalves and flows to the venturi tube to cause adverse yarn processingconditions. The present invention is a solution for controlling lowpressure seeping gases in a processing system.

It is an object of the invention to provide a valve means adapted tovent low pressure gases.

Another object of the invention is to provide a valve including a gasvent means.

Another further object is to provide a supplemental gas bleed device fora leaking valve system.

Another object is to provide a vent valve adapted to bleed-off lowpressure gases when seated and to permit flow of gases therepast whenunseated.

According to the invention, the novel vent valve comprises a valvehousing or body having a bore providing an opening extendingtherethrough with respective inlet and outlet ends. A valve member isslidably positioned in the bore and is normally biased by resilientmeans sealingly against a valve seat formed in the valve housing bore.The valve member is peripherally grooved or fluted to permit the flow ofgas past the valve member when the latter is unseated against the forceof the resilient means.

The valve member and housing each are provided with a vent passagewhich, when the valve member is seated, are aligned to open the intakeend of the bore opening to atmosphere. Thus, when the vent valve isconnected within United States Patent 0 "ice a gas system and there isseepage of gas, the seeping gases are vented from the system. When thevalve member is unseated by the build up of gas pressure against thevalve member overcoming the force of the resilient means, the valve ventpassage and the housing passage become misaligned and thereby disconnectthe intake end of the bore opening from atmosphere.

A better understanding of the invention will be gained by referring tothe more complete description that follows and to the accompanyingdrawing. In the drawing,

FIGURE 1 is a cross-section view of the vent valve embodying theinvention shown in a seated position and further representeddiagrammatically in association with an off-on valve and a conditionertube,

FIGURE 2 is a cross-section view of the vent valve in an unseatedposition, and

FIGURE 3 is an exploded view of the novel vent valve.

Referring to FIGS. 1-3 in the drawing, the novel vent valve 1 is shownconnected by a conduit 2 to a steam off-on valve 3 at the upstream orleft side of vent valve 1 and by a conduit 4 to a steam conditioningtube 5 for conditioning yarns and filaments 6 passing therethrough atthe downstream or right side thereof.

Vent valve 1 comprises a valve body or housing 7 with a bore 8 definedtherein providing a bore opening or passage 9 therethrough having aninlet end at the upstream side of the valve and an outlet end at thedownstream side of the valve. A valve seat 10 and a shoulder 11, spacedfrom seat 10, are defined in bore 8. A valve member 12 is slidablypositioned in bore 8 between seat 10 and shoulder 11. Valve member 12has a valve seating surface 13 complementary to the surface of valveseat 10. Valve member 12 is normally biased to a seated position on seat10 by a spring 14 compressed and retained between the valve member 12and shoulder 11. Spring 14 and one end thereof'abuts against valvemember 12, opposite the seating surface 13 thereof, and at its oppositeend abuts against shoulder 11. A plurality of spaced grooves or flutes15 extend axially or longitudinally and continuously along the fulllength of the periphery of valve member 12, and extend through the outerportion of seating surface 13 adjacent to the periphereal surface ofmember 12.

A vent passage or port 16 extends through the wall of valve body 7 andanother vent passage 17 extends through valve member 12. Vent passage 17is open at one end thereof to the inlet end of bore opening 9 and at itsopposite end is open to vent port or passage 16 when valve member 12 isbiased by spring 14 to its seated position, shown in FIG. 1,.so that theinlet side of opening 9 is open to atmosphere.

A thrust screw 18 extends threadingly through the side Wall of housing 7and extends into contact with a recessed portion or keyway 19 formed onvalve member 12. Preferably, screw 18 has a bore therein with a spring20 and a slidable plug 21 assembled in the screw bore. Plug 21-contactsthe recessed portion 19 and applies a side thrust to the valve member 12to maintain axial alignment thereof. The recessed portion 19 terminatesat one side thereof in a shoulder 22. When the valve member 12 isdisplaced by the pressure of a gas against the force of spring 14 acertain distance to the right, FIG. 2, shoulder 22 contacts thrust screw18 and constrains or limits further movement of valve member 12.

In operation, assume that valve member 12 is biased to a seated positionby spring 14 and vent passages 16 and 17 are aligned to vent the inletside of bore opening 9 to atmosphere as shown in FIG. 1. Assume further,that a yarn 6 being processed without steam is passing through theconditioner tube 5 and that the off-on valve 3 is in an off position butthat steam is seeping or escaping therepast and bowing to the upstreamor inlet side of bore opening 9. The seeping steam will then be ventedto atmosphere through vent passages 16 and 17. It will be understoodthat vent passages 16 and 17 are sized to permit seeping gases of lowpressures only to vent restrictively to atmosphere. Spring 14 is of achosen value to normally bias valve member 12 to a closed position untila certain working pressure above that of the seeping gas is exertedagainst the valve member 12.

Assume now, that it is desired to steam condition the yarn 6 passingthrough the steam conditioner 5. In this case, the off-on valve 3 ismoved to the on position and steam will flow to the inlet end of opening9. Since the vent passages 16 and 17 are small, the pressure of thesteam will build up in the inlet end of opening 9 and will act againstthe valve member 12. When suflicient pressure is built up to overcomethe force of spring 14, the valve member 12 will be pushed slidingly tothe right (FIG. 2) unseating member 12 and permitting steam to passthrough the vent valve 1 via flutes 15 of valve member 12 and to flow tothe conditioner tube 5. Passages 16 and 17 become misaligned when valvemember 12 is slightly unseated thereby closing off the inlet side ofopening 9 fioni atmosphere. Movement of valve member 12 rightward islimited by contact of shoulder 22 of recess 19 with thrust screw 18(FIG. 2).

When the off-on steam valve 3 is placed in the OE position, the pressureof the steam will decrease and spring 14 will return valve member 12 toits seated position. Thus, the yarn process is protected against harmfulseeping gases.

It will be understood that variations and modifications in structurefrom the illustrated embodiment of the invention are expected to becovered Within the spirit of abutment means defined in said bore nearsaid outlet end,

a valve member slidably positioned in said bore be tween said valve seatand said abutment means, said valve member provided with a seatingsurface at one end thereof complementary to said valve seat and providedwith spaced, longitudinal grooves extending continuously along theperipheral length thereof,

bias means having one end thereof acting against said valve member andthe opposite end thereof acting against said abutment means in saidbore,

a fluid bleed vent port extending through the wall of said valve bodyand open to atmosphere at all times,

a fluid bleed vent passage in said valve member, said vent passage beingopen at one end to the inlet end of said bore and open at its oppositeend to said vent port when said valve member is biased to a seatedposition by said bias means for bleeding restrictively low pressurefluid from the inlet end of said bore to atmosphere, and said vent portbeing disconnected from communication with said vent passage by saidvalve member when the latter is unseated by a fluid pressure build-up insaid inlet end of said bore, permitting fluid to flow through saidlongitudinal grooves past said valve member to said outlet end of saidbore.

2. A vent valve as in claim 1, further comprising means for limiting theopen position and for maintaining axial alignment of said valve member.

References Cited UNITED STATES PATENTS 2,468,960 5/1949 Case 1371162,733,729 2/1956 Wolfe 251297 XR 2,968,317 1/1961 Jay 1371l9 XR WILLIAMF. ODEA, Primary Examiner. H. M. COHN, Assistant Examiner.

U.S. Cl. X.R.

